plasmas alex friedman this work was performed under the auspices of the u.s. department of energy by...
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Plasmas
Alex FriedmanThis work was performed under the auspices of the U.S. Department of Energy by the University of California Lawrence Livermore National Laboratory under Contract Number W-7405-Eng-48.It is LLNL Report Number UCRL-PRES-23098, and may be obtained in Powerpoint form at: http://hifweb.lbl.gov/public/slides/Friedman-Plasma-Grades3-5-rev4.ppt … or in PDF (Adobe Acrobat) form at: http://hifweb.lbl.gov/public/slides/Friedman-Plasma-Grades3-5-rev4.pdf
Plasma is the 4th state of matter
A plasma is a collection of charged particles
- charge = electrons+ charge = ions = atoms whose electrons have been ripped off
Plasmas behave differently than gases
In a regular gas, the atoms move in straight lines until they bang into each other.
In a plasma, the ions and electrons push and pull on each other all the time.
Particles with the same charge repel each other.
Electrons push other electrons away, and ions push other ions away.
Particles with opposite charges are attracted to each other.
Ions pull on electrons, and electrons pull on ions.
+ +
+
- -
-
Plasma balls contain helium, neon, argon, and other gases.
When the power is switched on, some of the gas atoms have their electrons ripped from them.
This produces a plasma.
The sun is a plasma, burning with fusion “fire”
Plasma fills the universe
Catseye Nebula
Bug nebula
Carina nebula
Rosette nebula
Thor’s helmet
Fireworks and a comet and lightning, all at once!
Auroras (northern lights) are plasmas 100 miles up
Between sun and earth is plasma
Plasmas respond to electric and
magnetic forces
(this is a solar prominence)
~ 40 keV
~ 1 keV
~ 100 eV
~ 13.6 eV
~ 1 eV
~ 0.027 eV
ionization of H
-280 °F = -173 °C = 100 °K
1,340 °F = 727 °C = 1,000 °K
17,500 °F ≈ 9,700 °C ≈ 10,000 °K
180,000 °F ≈ 100,000 °C or °K
1,800,000 °F ≈ 1,000,000 °C or °K
18,000,000 °F ≈ 10,000,000 °C or °K
180,000,000 °F ≈ 100,000,000 °C or °K
1,800,000,000 °F ≈ 1,000,000,000 °C or °K
Matter is in the plasma state when it is hot enough, and not too tightly packed
C
“scientific notation” uses 1033 to mean 10 followed by 33 zeros
Fusion occurs when light ions are joined together to make a heavier ion. This releases energy.
Fusion power plants will “fuse” two kinds of Hydrogen …
Deuterium (D) + Tritium (T) Helium (He) + neutron (n) + energy
To fuse, the ions have to be hot enough (moving fast enough); they are a plasma
To make a lot of energy, this plasma must be kept together long enough for a lot of it to burn
“Beams” of ions are plasmas, too
They are “non-neutral plasmas” because they contain only a few electrons.
But - sometimes too many electrons sneak in and cause trouble!
The Heavy Ion Fusion Science Virtual National Laboratory
power plant uses the heat to make electricity
ion beams heat the targets and ignite a fusion “burn”
targets containing D and T are sent flying into a metal room
We are trying to use beams of heavy ions to create small fusion fires (little stars), one after the other
The Heavy Ion Fusion Science Virtual National Laboratory
In our experiments, we’re studying how ion beams behave, and how they heat matter
My group uses computer simulations to study ion beams
0. 1.5-7.5
7.5
0.5 1.0Z (m)
X (mm)
The Heavy Ion Fusion Science Virtual National Laboratory
We just learned that we will be able to build a new ion beam accelerator, called NDCX-II
We have talked about several things
• Plasmas - collections of charged particles whizzing around while pushing and pulling on each other
• Fusion - smashing together light ions in a plasma to make heavier ions, and energy
• Heavy Ion Fusion, using beams of heavy ions to heat plasma and make electricity - what we are trying to do
• Computer simulations of ion beams - my own work
Thanks for your attention
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